help with piezos

[vlad335]

Greetings

I am in the process of putting together a PA and reading things on this site, I am interested in using some piezos for the top end.

Right now, I have 4 Klipsch MWM subs, 2 horn mids with EV 12's, and Peavey midrange horns with comp drivers. I was thinking that some high end sizzle wouldn't hurt ( Crossover say, 7500 K ) After reading this site, I would like to build boxes and load some cheap piezos in them.

What would be the best piezos for this application? Looking at the parts Express site, I was thinking of 8 goldwood 1016's per box. ( Like the price!) firing downward slightly, sitting up about 7 feet in the air.

How would these be wired to be 8 ohms per box? Any ideas on box design?

Heres a pic of my Pa speakers minus one sub and the spacers that go in between the subs/mids.



I don't have any power amps yet but I am working on it. Any help would be greatly appreciated!

[LelandCrooks]

Any help would be greatly appreciated!

I sell forklifts.

How would these be wired to be 8 ohms per box? Any ideas on box design?

Piezos are a capacitive load. They don't show impedance per se to the amplifier. I'd wire them 4 in parallel, 2 banks in series. Vertical box, just like in the cabs you see here.

I see that's an ebay link. Did you just buy this? And if so, your back and billfold would have been better off building something from here. Really old school tech. Doesn't mean it can't sound good, but as stated earlier, I sell forklifts.

[vlad335]

Ha Ha! Yeah, their big and heavy I know but I got them for an incredible price. The guy selling was very local and practically had to give them away because they ain't gettin shipped. I had posted a link on another forum to the completed ebay auction and believe it or not, I had 2 guys contact me thru ebay wanting to buy these.

I downloaded the plans for the titan 48's and plan to build them too. Unfortunately I discovered this site after I bought the "wall o' sound" Maybe some Dr tops too when I get the money. Problem is, I am poor and want bang for the buck and this Klipsch system for what I paid, will give that in spades. We are talking the price of building a single T-48

You mention a vertical box... What plan here would best typlify this arrangement?

Oh, and thanks for the reply!

[Dave Non-Zero]

hey at least its all horn loaded. you are on the right track! heehee.

[LelandCrooks]

Just build a box wide enough to hold the drivers vertically, deep enough to hold them. Cut and glue the drivers to shorten the array. Like on an omni, or otop. You'll have to rig a base to hold it vertical on top of the stack.

Did I mention I sell forklifts

[Tim A]

Are those PV MF1-X horns? I can't imagine needing any more high end than that. I had a pair of those back in the day. They were designed to go on top of PV's Tri amp system, with a Midbass box and a bass bin below them. This was back before subs. If memory serves they handle about 150w. Before you jump into building a piezo array, I'd get a power amp and crossover and listen to them first.

BTW, when you set the system up, make sure you stack the PV's, don't set them side-by-side.

I can guess that unless you find a way to low-pass the PV's you're going to get a LOT of overlap between them and the piezos, which might make the highs sound like crap. And if you do decide to build a piezo box, they'll need to be vertical, not horizontal.

I think I'd up Leland's bid from 8 piezos to 12.

YEESH. My back hurts just looking at that setup.

[Bill Fitzmaurice]

I had 2 guys contact me thru ebay wanting to buy these.

Take the money and run before they come to their senses. I'd dump that stuff. Perhaps the drivers can be salvaged, but judging by the age of the system probably not, as they're likely all obsolete. The subs aren't really subs, as the horn is too short to go below 60 Hz at best. The midbasses and HF horns are at least three times the size required for their passbands. Dinosaurs, in every sense of the word. I don't want to rub salt into the wound, but there's a lesson to be learned here, and that's to do extensive research before you buy, not afterward.

[vlad335]

Well I guess this system sucks but it's all I can afford right now. I am looking locally for some used poweramps as well so it can all be put together and get out playing.

I was also thinking of getting this behringer crossover unit and EQ.
http://www.americanmusical.com/item--i-BEH-DCX2496.html
http://www.americanmusical.com/Item--i-BEH-DEQ2496.html

We have access to a large area that we can set this system up in and try to tweak the crap out of it using the above units and my laptop. What do you think?

Since I can't possibly build a system from the ground up right now, maybe a couple subs ( T-48's ) will fill the hole as the first upgrade, then go from there? Maybe just using 2 of the Klipsch as mid bass in a 4 way system.

[LelandCrooks]

They're both good pieces. I run a deq, lots of folks around here run the dcx. With tight money just buy the dcx. Use the other funds on better amplifiers, or to start building. You can get along without the deq, it's a tool that will let you tweak to your heart's content. The dcx is a must have, at least some kind of crossover is. The dcx has enough basic tools to get you started by itself.

[Tim A]

Since I can't possibly build a system from the ground up right now, maybe a couple subs ( T-48's ) will fill the hole as the first upgrade, then go from there?

That's actually a good plan. Dump those way too big bass bins and use the money to build a couple of T-48's. The mid and top cabs you have would be fine to get started.

If you can get both Behringer units, do so. If only one, get the crossover, it's a must-have.

[vlad335]

Thanks for the help guys! I actually added the Behringer units into my shopping cart at AMS at first because of the price. Searches on google brought alot of good things said about these units.

Admittingly, I was feeling like I got kicked in the teeth after Bill's reply. However, I have to start somewhere and I think I can get the most from this system until I slowly replace it. T-48's are the first order of business then some DR280's.

I do need to say this... I heard these same Klipsch speakers in the 80's and never forgot it. My band played a ski resort called Seven Springs along with another band called The Knightriders for the entire winter. They used these horns and their low end was so powerful. If I could sum it up in one word, it was effortless, like nothing I had ever heard. I did make a mental note at the time that they jammed one stack against the wall so maybe that helped the deep low end response in the particular room we shared. This experience was a major factor with me jumping on this ebay auction.

Every band I have heard since around here are using ported 15's or 18's and powering them with mega wattage. This bass sounds stressed to me at any volume. Almost like a seperate entity by itself and not really part of the music. The secret to the sound I once heard has got to be horns.

I am excited about building the T-48's and thankful that I inadvertantly found this site and Bill's plans

[Sydney]

Every band I have heard since around here are using ported 15's or 18's and powering them with mega wattage.

As a neighbor ( OK, about a hundred miles south ) I can confirm your observation.
Just yesterday I saw a system for a local fair ( provided by the largest PA company in WV ). It consisted of JBL's in reflex boxes placed on the street in 2 stacks, 30 feet apart ( like a giant stereo ). Driven by a 10k Yamaha board and loads of Crown amps.
New equipment - bad set up.
Your Klipsch stuff may not be SOTA - but it still better than a lot of new crap-inna-box stuff, that is bought and used daily.
Your phaseout plan will allow you to compare old horn design with new horn design.
( Don't feel slighted, Mr Fitzmaurice's master plan is to have the whole world using his designs )

[bgavin]

Every band I have heard since around here are using ported 15's or 18's and powering them with mega wattage.

This is a dead end.

I have an Eminence Magnum 18LF in optimal SBB4 vented alignment and compared it to my 8" MCM 55-2421 driven home theater horn. The MCM beats the crap out of the 18" Magnum. The MCM is much louder and goes down deeper.